Placards must be at least how many inches on each side?
Correct. Placards are diamond-shaped, at least 250 mm (about 10.75 inches) on each side.
CDL Practice Question #232
Category: Hazmat
Why this question matters
This question is one of 68 in our Hazmat bank. The reasoning above comes directly from the AAMVA CDL Manual, the source document used by every U.S. state DMV. Memorizing the underlying rule — not just the letter answer — is what separates passing on the first attempt from a return trip and another fee.